Reflux condenser system for improved fluids separation

ABSTRACT

An improved condenser system employing heat exchange tubes that are supported by rod-type baffles. The condenser system can be a reflux condenser positioned at the top of a distillation column and employing a generally upright U-tube bundle for cooling fluids exiting the top of the distillation column.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates generally to condensers. In anotheraspect, the invention relates to reflux condensers employed at the topof distillation towers. In a further aspect, the invention relates to analkylation unit employing an improved rectifier for separating n-butanefrom alkylate.

[0003] 2. Discussion of the Prior Art

[0004] For many years, reflux condensers have been employed at the topof distillation towers to condense high boiling point fluids mixed withthe low boiling point vapors exiting the top of the tower. Referring toFIG. 1, a conventional reflux condenser 10 employed at the top of adistillation tower typically includes a condensing zone 12 having alower condensing zone inlet 14 for receiving upwardly flowing fluidsfrom the top of the distillation tower and an upper condensing zoneoutlet 16 for discharging gaseous fluids from the reflux condenser 10. AU-tube bundle 18 is disposed in the condensing zone 12. The open ends ofthe individual U-tubes 20 in U-tube bundle 18 fluidly communicate with acooling fluid inlet 22 and a cooling fluid outlet 24 so that a coolingfluid can flow continuously through the U-tubes 20. When the upwardlyflowing gaseous fluids from the top of the distillation tower contactthe cool U-tubes 20 in the condensing zone 12, the high boiling pointcomponent(s) of the fluids condense.

[0005] In the conventional reflux condenser 10, the individual U-tubes20 of U-tube bundle 18 are supported relative to one another via aplurality of horizontally disposed plate-type baffles 26. It has beendiscovered that the use of such plate-type baffles 26 in the refluxcondenser 10 presents a number of drawbacks. For example, the velocityprofile of the fluid flowing upwardly through the condensing zone 12 isnon-uniform due to the configuration of the plate-type baffles 26.Further, the flat upper surfaces of the plate-type baffles 26 presentareas where “pooling” of condensed liquids can occur. The pooled liquidsfrom the flat upper surfaces of the plate-type baffles 26 can drip offof the plate-type baffles 26 and become entrained in the high velocityfluids flowing upwardly through the reflux condenser 10. The entrainedliquids can then be carried out of the reflux condenser 10 through thecondensing zone outlet 16. When a significant amount of the entrained,condensed liquids exits the reflux condenser 10 through the condensingzone outlet 16, the main function of the reflux condenser 10 (i.e.,condensing and separating high boiling point fluids from low boilingpoint fluids) is frustrated.

OBJECTS AND SUMMARY OF THE INVENTION

[0006] Responsive to these and other problems, it is an object of thepresent invention to provide a condenser which more efficientlycondenses and separates high boiling point fluids from low boiling pointfluids.

[0007] A further object of the present invention is to provide a refluxcondenser employing tube-supporting baffles that present little or noflat upper surfaces where condensed liquids can pool.

[0008] Another object of the present invention is to provide a refluxcondenser that allows for a substantially uniform velocity profile ofthe fluids flowing upwardly therethrough.

[0009] Still another object of the present invention is to provide areflux condenser that minimizes the maximum velocity of upwardly flowingfluids so that condensed liquids do not become entrained in the upwardlyflowing fluids.

[0010] Yet another object of the present invention is to provide areflux condenser which separates liquids entrained in gaseous fluidsflowing through the reflux condenser before the gaseous fluids exit thereflux condenser.

[0011] It should be noted that not all of the above-listed objects needbe accomplished by the present invention, and other objects andadvantages of the invention will be apparent from the writtendescription and drawings.

[0012] Accordingly, in one embodiment of the present invention, acondenser is provided that comprises a main body and a generally uprightU-tube bundle. The main body defines a condensing zone. The U-tubebundle is disposed in the condensing zone and comprises a plurality ofU-tubes and a plurality of rod-type baffles for supporting the U-tubes.

[0013] In accordance with another embodiment of the present invention,there is provided a distillation unit which comprises an elongatedupright distillation column and a reflux condenser. The distillationcolumn has a lower end and an upper end and defines a fractionation zoneextending between the lower and upper ends. The reflux condenser ispositioned above and rigidly coupled to the upper end of thedistillation column and defines a condensing zone fluidly communicatingwith the fractionation zone via a condensing zone inlet. The condenserincludes a heat exchange tube bundle disposed in the condensing zone andcomprising a plurality of upright elongated heat exchange tubes and aplurality of rod-type baffles for supporting the heat exchange tubes.

[0014] In still another embodiment of the present invention, there isprovided an alkylation unit comprising a reactor, a depropanizer, and arectifier. The reactor is operable. to contact an iso-paraffin, anolefin, and an acid catalyst under reaction conditions sufficient toproduce a reactor effluent comprising an alkylate, propane, andn-butane. The depropanizer fluidly communicates with the reactor and isoperable to substantially separate the propane and the alkylate. Therectifier fluidly communicates with the depropanizer and is operable toseparate at least a portion of the n-butane from the alkylate and returnthe resulting separated alkylate to the depropanizer. The rectifierincludes an elongated upright distillation column and a refluxcondenser. The condenser includes a main body defining a condensing zoneand a heat exchange tube bundle disposed in the condensing zone. Theheat exchange tube bundle comprises a plurality of elongated heatexchange tubes and a plurality of rod-type baffles for supporting theheat exchange tubes.

[0015] In yet another embodiment of the present invention, a process isprovided that comprises the steps of: (a) fractionating a fluid mixturein an upright distillation column; (b) conducting a light fluidcomponent of the fluid mixture to a reflux condenser rigidly coupled tothe top of the distillation column, wherein the condenser includes aplurality of heat exchange tubes supported by a plurality of rod-typebaffles; and (c) condensing a heavy fluid component of the light fluidcomponent in the condenser, thereby providing a condensed liquid in thecondenser.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

[0016] Preferred embodiments of the present invention are described indetail below with reference to the attached drawing figures, wherein:

[0017]FIG. 1 is a partial sectional side view of a conventional refluxcondenser, particularly illustrating the plate-type baffles that supportthe heat exchange tubes;

[0018]FIG. 2 is a side view of a distillation unit including an uprightelongated distillation column and a reflux condenser coupled to the topof the distillation column;

[0019]FIG. 3 is a partial sectional side view of a reflux condenserconstructed in accordance with the principles of the present invention,particularly illustrating a U-tube bundle comprising a plurality ofrod-type baffles for supporting the U-tubes;

[0020]FIG. 4 is a sectional top view of the reflux condenser taken alongline 4-4 in FIG. 3, particularly illustrating the components of theU-tube bundle and the mist extraction pad positioned proximate theoutlet of the reflux condenser;

[0021]FIG. 5 is a top view of a group of rod-type baffles coupled to asingle baffle ring;

[0022]FIG. 6 is a partial isometric view of a segment of a single U-tubeleg and four adjacent vertically spaced rod-type baffles, particularlyillustrating the positive four-point containment system provided by therod-type baffles; and

[0023]FIG. 7 is a schematic diagram of an alkylation unit employing arectifier that takes full advantage of the benefits provided by thenovel reflux condenser described herein.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] Referring initially to FIG. 2, a distillation unit 100 isillustrated as generally comprising an elongated upright distillationcolumn 102 and a reflux condenser 104. Distillation column 102 presentsa lower end 106 and an upper end 108 and defines a interiorfractionation zone extending between lower and upper ends 106, 108.Distillation column 102 includes an inlet 1 10 vertically positionedbetween lower and upper ends 106, 108 and fluidly communicating with thefractionation zone. In operation, a substantially gaseous heated fluidmixture enters the fractionation zone via inlet 1 10. In thefractionation zone, the fluid mixture is fractionated into variouscomponents and withdrawn from the fractionation zone according to theboiling point of the components. Generally, heavier (i.e., higherboiling point) fluid components condense toward lower end 106 ofdistillation column 102 while the lightest (i.e., lowest boiling point)fluid components do not condense in the fractionation zone and flowupwardly out of upper end 108 and into reflux condenser 104. Any heavyfluid components remaining in the light fluid component flowing throughreflux condenser 104 are condensed in reflux condenser 104. Thecondensed liquids in reflux condenser 104 are then allowed to flowdownwardly into the fractionation zone of distillation column 102 bygravitational force.

[0025] Referring now to FIG. 3, reflux condenser 104 includes a mainbody 112 and a generally upright U-tube bundle 114. Main body 112defines a condensing zone 116 having a lower condensing zone inlet 118which fluidly communicates with the upper end of the fractionation zonedefined by distillation column 102 (shown in FIG. 3) and an uppercondensing zone outlet 120 through which fluids exit condensing zone116. Upright U-tube bundle 114 is disposed in condensing zone 116 andextends at least partly into the flow path of fluids flowing fromcondensing zone inlet 118 to condensing zone outlet 120 so that thefluids flowing through condensing zone 116 contact the outer surface ofthe plurality of individual U-tubes 122 of U-tube bundle 114. As usedherein, the term “U-tube” denotes a continuous tube formed generally inthe shape of a “U” and having a pair of open ends. As used herein, theterm “upright U-tube bundle” denotes a group of individual U-tubes and asupport system that supports the U-tubes in a manner such that the sides(i.e., legs) of the individual U-tubes are substantially upright and areopen at their top ends.

[0026] Main body 112 of reflux condenser 104 further defines a coolingfluid manifold 124 which is positioned generally above, and fluidlyisolated from, condensing zone 116. Cooling fluid manifold 124 isdivided into an inlet portion 126 and an outlet portion 128. Inletportion 126 receives a cooling fluid via a cooling fluid inlet 130defined by main body 112. Outlet portion 128 discharges the coolingfluid through a cooling fluid outlet 134 defined by main body 112. Inletportion 126 fluidly communicates with the open inlet ends of U-tubes 122and outlet portion 128 fluidly communicates with the opposite openoutlet ends of U-tubes 122. Inlet and outlet portions 126, 128 arefluidly isolated from one another, except for the fluid flowcommunication provided therebetween by U-tubes 122.

[0027] Referring to FIGS. 3 and 4, U-tube bundle 114 generally comprisesU-tubes 122, a plurality of rod-type baffles 134, and a plurality ofvertically spaced, generally horizontally disposed baffle rings 136 a-e(shown in FIG. 3). Baffle rings 136 a-e and rod-type baffles 134cooperate to rigidly support U-tubes 122 relative to main body 112. Asused herein, the term “rod-type baffle” shall denote an elongated bafflemember whose axial cross section shows an outer surface with nosubstantially flat portions. Generally, rod-type baffles 134 will berods having substantially cylindrical or elliptical axial crosssections.

[0028] Referring now to FIG. 5, a group of laterally spaced, parallellyextending rod-type baffles 134 a are associated with each baffle ring136 a. Preferably, the ends of baffles 134 a are rigidly coupled tobaffle ring 136 a so that baffles 134 a extend chordally across the opencenter baffle ring 136 a. Referring to FIGS. 3-5, it is preferred forthe separate groups of parallel baffles 134 that are coupled to adjacentvertically spaced baffle rings 136 (e.g., rings 136 a and 136 b) toextend substantially perpendicular to one another. Thus, the groups ofbaffles 134 that are coupled to every other vertically spaced bafflering 136 (e.g., rings 136 a and 136 c) extend substantially parallel toone another. It is preferred for the groups of rod-type baffles 134 thatare coupled to every other vertically spaced baffle ring 136 (e.g.,rings 136 a and 136 c) to contact each U-tube 122 on generally oppositesides of U-tube 122, thereby forming a positive four-point containmentsystem for supporting each U-tube 122.

[0029] Referring now to FIG. 5, the positive four-point containmentsystem formed by four vertically spaced rod-type baffles 134 a-d isillustrated as supporting a section of one leg of U-tube 122. As usedherein, the term “positive four-point containment system” shall denote asystem for supporting a heat exchange tube cooperatively employing atleast four rod-type baffles that contact the tube and are axially spacedalong the tube, wherein adjacent axially spaced baffles extendsubstantially perpendicular to one another and alternating axiallyspaced baffles contact generally opposite sides of the tube.

[0030] Referring again to FIGS. 3-6, employing rod-type baffles in sucha positive four-point containment system provides reflux condenser 104with minimal flow-induced U-tube 122 vibration, uniform fluid velocityprofile in condensing zone 116, enhanced heat transfer due to turbulencecaused by rod-type baffles 134, no flat baffle surfaces on whichcondensed liquids can pool, and reduced entrainment of condensed liquidsdue to low fluid velocities.

[0031] Referring again to FIGS. 3 and 4, a mist extraction pad 138 ispreferably disposed in condensing zone 116 and covers condensing zoneoutlet 120. Mist extraction pad 138 is made of a porous material throughwhich the gaseous fluids exiting condensing zone 116 may pass. Mistextraction pad 138 is preferably operable to cause coalescence of liquiddroplets (i.e., mist) entrained in the gaseous fluids exiting condensingzone 116 on elements of mist extraction pad 138. The coalesced liquidscan then drain downwardly from mist extraction pad 138, throughcondensing zone 116, and into distillation column 102 by gravitationalforce. Mist extraction pad 138 is preferably a commercially availablewire mesh mist extraction pad such as, for example, the Metex Opti-Mesh™mist eliminator available from Metex Corporation, Edison, N.J., U.S.A.

[0032] Referring again to FIGS. 2-4, during operation of refluxcondenser 104, a cooling fluid (e.g., 40-125° F. water) continuouslyflows through U-tubes 122 while a light fluid component flows generallyupwardly through condensing zone 116. When the light fluid componentcontacts and is cooled by U-tubes 122, a heavy fluid component of thelight fluid component condenses in condensing zone 116. The condensedfluid then flows downwardly from condensing zone 116 into distillationcolumn 102 via condensing zone inlet 118. In order to prevent thevelocity of fluids flowing upwardly through condensing zone inlet 118from being high enough to cause entrainment of the downwardly flowingcondensed liquids therein, it is preferred for the minimum horizontalopen area of condensing zone inlet 118 to be at least 50 percent of themaximum horizontal open area of condensing zone 116. As used herein, theterm “horizontal open area” shall denote the total area of an openingtaken along a horizontal cross-sectional line through the opening.Preferably, the minimum horizontal open area of condensing zone inlet118 is at least 75 percent of the maximum horizontal open area ofcondensing zone 116, most preferably the minimum horizontal open area ofcondensing zone 118 is at least 80 percent of the maximum horizontalopen area of condensing zone 116.

[0033] Referring now to FIG. 7, an alkylation unit 200 is illustrated asgenerally comprising a reactor 202, a catalyst regenerator 204, adepropanizer 206, and a rectifier 208. In reactor 202, an iso-butanestream and an olefin (e.g., butylene and/or propylene) stream arecontacted in the presence of an acid catalyst (e.g., hydrofluoric acid)to thereby provide a deactivated acid catalyst and a reactor effluent.The deactivated catalyst can be cycled through catalyst regenerator 204in order to reactivate the catalyst. The reactor effluent typicallycomprises an alkylate, propane, iso-butane, and normal-butane(n-butane). As used herein, the term “alkylate” denotes an alkylationreaction product primarily comprising C₅+hydrocarbons that boil in thegasoline boiling range and have an end point between 375 and 450° F. Thereactor effluent is sent to depropanizer 206 for separation of thepropane and iso-butane from the alkylate. Depropanizer 206 can be anyconventional fractional distillation tower typically used in alkylationunits for separating propane from alkylate.

[0034] Rectifier 208 is fluidly coupled to depropanizer 206 and isoperable to remove a “side draw” of fluid, primarily comprising alkylateand n-butane, from depropanizer 206. Rectifier 208 generally includes adistillation column 210 and a reflux condenser 212. Preferably,rectifier 208 is constructed in the same manner as distillation unit100, described above with reference to FIGS. 2-6. In distillation column210, substantially all of the alkylate is separated from the n-butane.In reflux condenser 212, any alkylate remaining in the upwardly flowingn-butane stream is condensed and drains back into distillation column210 for return to depropanizer 206.

[0035] The preferred forms of the invention described above are to beused as illustration only, and should not be used in a limiting sense tointerpret the scope of the present invention. Obvious modifications tothe exemplary embodiments, set forth above, could be readily made bythose skilled in the art without departing from the spirit of thepresent invention.

[0036] The inventors hereby state their intent to rely on the Doctrineof Equivalents to determine and assess the reasonably fair scope of thepresent invention as pertains to any apparatus not materially departingfrom but outside the literal scope of the invention as set forth in thefollowing claims.

What is claimed is:
 1. A condenser comprising: a main body defining acondensing zone; and a generally upright U-tube bundle disposed in thecondensing zone and comprising a plurality of U-tubes and a plurality ofrod-type baffles for supporting the U-tubes.
 2. A condenser according toclaim 1, said main body defining a condensing zone inlet fluidlycommunicating with the condensing zone and a condensing zone outletfluidly communicating with the condensing zone, said condensing zoneoutlet being vertically positioned higher than the condensing zoneinlet.
 3. A condenser according to claim 2, said U-tubes extending atleast partly between the condensing zone inlet and the condensing zoneoutlet.
 4. A condenser according to claim 2, said condensing zone inletpresenting a minimum horizontal open area which is at least 50 percentas large as the maximum horizontal open area of the condensing zone. 5.A condenser according to claim 1; and a mist extraction pad disposed insaid condensing zone and covering the condensing zone outlet, said mistextraction pad being operable to cause coalescence of at least a portionof a condensed liquid.
 6. A condenser according to claim 1, said mainbody defining a cooling fluid manifold disposed vertically above andfluidly isolated from the condensing zone, said fluid cooling manifoldincluding an inlet portion and an outlet portion fluidly communicatingwith one another via the U-tubes.
 7. A condenser according to claim 6,said main body defining a cooling fluid inlet fluidly communicating withsaid inlet portion and a cooling fluid outlet fluidly communicating withsaid outlet portion, each of said U-tubes including a first open endfluidly communicating with the inlet portion and a second open endfluidly communicating with the outlet portion.
 8. A condenser accordingto claim 1, said U-tube bundle including a plurality of verticallyspaced baffle rings, each of said baffle rings being rigidly coupled toa respective baffle group of said baffles.
 9. A condenser according toclaim 8, said baffles of each respective baffle group extendingsubstantially parallel to one another.
 10. A condenser according toclaim 9, said baffle rings and baffles being substantially horizontallyoriented.
 11. A condenser according to claim 10, said baffles ofadjacent vertically spaced baffle groups extending substantiallyperpendicular to one another.
 12. A condenser according to claim 8, saidbaffles of four adjacent vertically spaced adjacent baffle groupsforming a positive four-point containment system for supporting theU-tubes.
 13. A condenser according to claim 8, said baffle rings beingpositioned generally between the U-tubes and an upright side wall of themain body that defines at least a portion of the condensing zone, saidbaffle rings being operable to enhance the contacting between anupwardly flowing fluid and the U-tubes by at least substantiallypreventing bypass flow of the fluid between the sidewall and theU-tubes.
 14. A distillation unit comprising: an elongated uprightdistillation column having a lower end and an upper end and defining afractionation zone extending between the lower and upper ends; and areflux condenser positioned above and rigidly coupled to the upper endof the column and defining a condensing zone fluidly communicating withthe fractionation zone via a condensing zone inlet, said condenserincluding a heat exchange tube bundle disposed in the condensing zoneand comprising a plurality of upright elongated heat exchange tubes anda plurality of rod-type baffles for supporting the heat exchange tubes.15. A distillation unit according to claim 14, said condenser includinga main body defining the condensing zone, the condensing zone inlet, anda condensing zone outlet fluidly communicating with the condensing zone,said condensing zone outlet being vertically positioned higher than thecondensing zone inlet.
 16. A distillation unit according to claim 14,said heat exchange tube bundle further comprising a plurality ofvertically spaced baffle rings, each of said baffle rings being rigidlycoupled to a respective baffle group of said baffles.
 17. A distillationunit according to claim 16, said baffles of four adjacent verticallyspaced baffle groups forming a positive four-point containment systemfor supporting the heat exchange tubes.
 18. A distillation unitaccording to claim 14, said heat exchange tubes being U-tubes.
 19. Adistillation unit according to claim 18, said condenser defining acooling fluid manifold disposed vertically above and fluidly isolatedfrom the condensing zone, said cooling fluid manifold including an inletportion and an outlet portion fluidly communicating with one another viaonly the U-tubes.
 20. A distillation unit according to claim 19, saidcondenser defining a cooling fluid inlet fluidly communicating with theinlet portion and a cooling fluid outlet fluidly communicating with theoutlet portion, each of the U-tubes including a first open end fluidlycommunicating with the inlet portion and a second open end fluidlycommunicating with the outlet portion.
 21. A distillation unit accordingto claim 14, said condensing zone inlet presenting a minimum horizontalopen area that is at least 50 percent as large as the maximum horizontalopen area of the condensing zone.
 22. An alkylation unit comprising: areactor for contacting an iso-paraffin, an olefin, and an acid catalystunder reaction conditions sufficient to produce a reactor effluentcomprising an alkylate, propane, and n-butane; a depropanizer fluidlycommunicating with the reactor and operable to substantially separatethe propane and the alkylate; and a rectifier fluidly communicating withthe depropanizer and operable to separate at least a portion of then-butane from the alkylate and return the resulting separated alkylateto the depropanizer, said rectifier including an elongated uprightdistillation column and a reflux condenser, said condenser including amain body defining a condensing zone and a heat exchange tube bundledisposed in the condensing zone, said heat exchange tube bundlecomprising a plurality of elongated heat exchange tubes and a pluralityof rod-type baffles for supporting the heat exchange tubes.
 23. Analkylation unit according to claim 22, said condenser being positionedgenerally above and rigidly coupled to the distillation column.
 24. Analkylation unit according to claim 22, said heat exchange tube bundlebeing a generally upright U-tube bundle.
 25. An alkylation unitaccording to claim 22, said distillation column defining a fractionationzone, said main body defining a condensing zone inlet for providingfluid communication between the condensing zone and the fractionationzone.
 26. An alkylation unit according to claim 25, said main bodydefining a condensing zone outlet fluidly communicating with thecondensing zone, said condensing zone outlet being vertically positionedhigher than the condensing zone inlet.
 27. An alkylation unit accordingto claim 22, said heat exchange tube bundle further comprising aplurality of vertically spaced baffle rings, each of said baffle ringsbeing rigidly coupled to a respective baffle group of said baffles. 28.An alkylation unit according to claim 27, said baffles of four adjacentvertically spaced baffle groups forming a positive four-pointcontainment system for supporting the heat exchange tubes.
 29. Analkylation unit according to claim 28, said heat exchange tubes beingU-tubes.
 30. An alkylation unit according to claim 29, said main bodydefining a cooling fluid manifold disposed vertically above and fluidlyisolated from the condensing zone, said cooling fluid manifold includingan inlet portion and an outlet portion fluidly communicating with oneanother via the U-tubes.
 31. An alkylation unit according to claim 30,said main body defining a cooling fluid inlet fluidly communicating withthe inlet portion and a cooling fluid outlet fluidly communicating withthe outlet portion, each of said U-tubes including a first open endfluidly communicating with the inlet portion and a second open endfluidly communicating with the outlet portion.
 32. A process comprisingthe steps of: (a) fractionating a fluid mixture in an uprightdistillation column; (b) conducting a light fluid component of the fluidmixture to a reflux condenser rigidly coupled to the top of thedistillation column, said condenser including a plurality of heatexchange tubes supported by a plurality of rod-type baffles; and (c)condensing a heavy fluid component of the light fluid component in thecondenser, thereby providing a condensed liquid in the condenser.
 33. Aprocess according to claim 32; and (d) allowing the condensed liquid toflow downwardly from the condenser into the distillation column bygravitational force.
 34. A process according to claim 32; and (e)passing at least a portion of the light fluid component through a mistextraction pad, thereby causing coalescence of liquid droplets of theheavy fluid component on the mist extraction pad.
 35. A processaccording to claim 32; and (f) reacting an iso-paraffin and an olefin inthe presence of an acid catalyst to thereby produce a reactor effluentcomprising the fluid mixture.
 36. A process according to claim 35; and(g) fractionating the reactor effluent in a fractionater.
 37. A processaccording to claim 36; and (h) transporting the fluid mixture from thefractionater to the distillation column.
 38. A process according toclaim 37; and (i) transporting at least a portion of the condensedliquid from the distillation column to the fractionater.
 39. A processaccording to claim 38, said reactor effluent comprising an alkylate,propane, n-butane, and iso-butane, said fluid mixture comprising thealkylate and n-butane, said condensed liquid comprising the alkylate.40. A process according to claim 32, said condenser comprising a mainbody defining a condensing zone, said heat exchange tubes being disposedin the condensing zone, said heat exchange tubes having a generallyupright orientation.
 41. A process according to claim 40, said main bodydefining a condensing zone inlet fluidly communicating with thecondensing zone and a condensing zone outlet fluidly communicating withthe condensing zone, said condensing zone outlet being verticallypositioned higher than the condensing zone inlet.
 42. A processaccording to claim 41, said condenser further including a plurality ofvertically spaced baffle rings, each of said baffle rings being rigidlycoupled to a respective baffle group of said baffles.
 43. A processaccording to claim 42, said baffles of four adjacent vertically spacedbaffle groups forming a positive four-point containment system forsupporting the heat exchange tubes.
 44. A process according to claim 43,said heat exchange tubes being U-tubes.